使用Vitamio打造自己的Android万能播放器（8）——细节优化

     public  static String showFileSize( long size) {
        String fileSize;
         if (size < KB)
            fileSize = size + "B";
         else  if (size < MB)
            fileSize = String.format("%.1f", size / KB) + "KB";
         else  if (size < GB)
            fileSize = String.format("%.1f", size / MB) + "MB";
         else
            fileSize = String.format("%.1f", size / GB) + "GB";

         return fileSize;
    }

     /**  显示SD卡剩余空间  */
     public  static String showFileAvailable() {
        String result = "";
         if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {
            StatFs sf =  new StatFs(Environment.getExternalStorageDirectory().getPath());
             long blockSize = sf.getBlockSize();
             long blockCount = sf.getBlockCount();
             long availCount = sf.getAvailableBlocks();
             return showFileSize(availCount * blockSize) + " / " + showFileSize(blockSize * blockCount);
        }
         return result;

           if (!mHistory.contains(url))
                mHistory.add(0, url);

     /**  删除文件  */
     private  void deleteFile( final FileAdapter adapter,  final PFile f,  final  int position) {
         new AlertDialog.Builder(getActivity()).setIcon(android.R.drawable.ic_dialog_alert).setTitle(R.string.file_delete).setMessage(getString(R.string.file_delete_confirm, f.title)).setNegativeButton(android.R.string.yes,  new DialogInterface.OnClickListener() {
            @Override
             public  void onClick(DialogInterface dialog,  int which) {
                 try {
                    File file =  new File(f.path);
                     if (file.canRead() && file.exists())
                        file.delete();
                    FileBusiness.deleteFile(getActivity(), f);
                    adapter.delete(position);
                }  catch (Exception e) {

                }
            }

        }).setPositiveButton(android.R.string.no,  null).show();
    }

     /**  重命名文件  */
     private  void renameFile( final FileAdapter adapter,  final PFile f,  final  int position) {
         final EditText et =  new EditText(getActivity());
        et.setText(f.title);
         new AlertDialog.Builder(getActivity()).setTitle(R.string.file_rename).setIcon(android.R.drawable.ic_dialog_info).setView(et).setNegativeButton(android.R.string.yes,  new DialogInterface.OnClickListener() {

            @Override
             public  void onClick(DialogInterface dialog,  int which) {
                String name = et.getText().toString().trim();
                 if (name ==  null || name.trim().equals("") || name.trim().equals(f.title))
                     return;

                 try {
                    File fromFile =  new File(f.path);
                    File nf =  new File(fromFile.getParent(), name.trim());
                     if (nf.exists()) {
                        Toast.makeText(getActivity(), R.string.file_rename_exists, Toast.LENGTH_LONG).show();
                    }  else  if (fromFile.renameTo(nf)) {
                        f.title = name;
                        f.path = nf.getPath();
                        FileBusiness.renameFile(getActivity(), f);
                        adapter.notifyDataSetChanged();
                    }
                }  catch (SecurityException se) {
                    Toast.makeText(getActivity(), R.string.file_rename_failed, Toast.LENGTH_LONG).show();
                }
            }

        }).setPositiveButton(android.R.string.no,  null).show();